Unit 2 APES topic questions

Based on the data shown in the graph, which of the following events occurred after the glacial retreat?

Primary succession explanation: The change in species over time following a disturbance is an example of primary succession.

Which of the following correctly describes the disruption of an ecosystem service by an anthropogenic activity?

Provisioning services are disrupted by the increased combustion of fossil fuels, which leads to an increase in air pollution. explanation: The combustion of fossil fuels is an anthropogenic activity that disrupts provisioning services.

Based on the data shown in the graph, which of the following best describes how ecologists could determine when this ecosystem is approaching a climax community?

Record the number and type of producers present every year after the eruption A high number of late successional plant species would indicate that the ecosystem is approaching a climax community.

Which of the following would be categorized as a cultural ecosystem service of forests?

Recreation and scenic areas for tourism explanation: Recreation and tourism are the nonmaterial or cultural ecosystem services of forests.

Which of the following explanations is best supported by the data shown in the map above?

Animals migrate seasonally to mate and to find food in different habitats. Animals migrate to more hospitable climates for food resources and for mating.

Which of the following was the number of finches in the population with a beak size of 10.2 mm in 1978?

12 Correct. Using the second graph, which shows the population distribution in 1978, the bar height is 12 individuals when the beak size measures 10.2 mm.

The graphs above show the population size and distribution of beak sizes in a finch population on the island of Daphne Major in the Galapagos in 1976 and 1978. Smaller-beaked finches are better suited for eating grasses and small seeds. Larger-beaked finches are better suited for cracking larger seeds and nuts. In 1977 a drought took place and the vegetation of the island was affected by the lack of rain. Which of the following was the average beak size of finches on the island of Daphne Major in 1976?

9.5 mm This average beak size for the population in 1976 is 9.5 mm based on the distribution of beak sizes in the graph. It is also noted with a dashed line.

Which of the following statements about levels of biodiversity is correct?

A population with high genetic biodiversity is better able to respond to environmental stressors. explanation: Genetic diversity is an important part of natural selection, as genetic variation is more likely to allow some individuals in a population to survive in a changing environment.

Highly specialized species tend to evolve on islands because of the environmental conditions and resource availability. Based on the theory of island biogeography, which of the following would most likely experience the greatest decline of specialist species if an invasive species emigrated from the mainland?

A small island in close proximity to the mainland explanation: Being close to the mainland increases immigration of species. A small island has fewer niches available and specialized food webs, which is most likely to cause substantial declines in specialist species.

Study Finds Aardvarks Suffering as African Climate Heats Up Little is known about Africa's elusive aardvarks, but new research says they are vulnerable to climate change like many other species. Hotter temperatures are taking their toll on the aardvark, whose diet of ants and termites is becoming scarcer in some areas because of reduced rainfall. Drought in the Kalahari Desert killed five out of six aardvarks that were being monitored for a year, as well as 11 others in the area. The aardvarks' body temperatures plummeted during the night because they were not getting enough energy from diminished food sources. They tried to conserve energy by looking for insects during the warmer daytime, but their efforts to adapt could not save them. Researchers said some birds, reptiles, and other animals use aardvark burrows to escape extreme temperatures, reproduce, and hide from predators. They could have fewer refuges available if aardvark populations shrink because of rising temperatures, they said. The aardvark, which lives in many parts of sub-Saharan Africa, is identified as an animal of "least concern" on an international "red list" of threatened species. There are no indications that the population is changing significantly in southern Africa, though it is speculated that numbers may be declining elsewhere because of habitat destruction, the bushmeat trade, and other factors. Which of the following best identifies the author's claim?

Aardvarks are a keystone species and their decline could have a trophic cascade effect on the ecosystem. The article states that many other species use burrows dug by aardvarks, indicating that a decline in aardvark numbers will have dramatic negative effects. Aardvarks are considered a keystone species because they play a critical role in the way the ecosystem functions.

Which of the following claims is best supported by the data in the graph?

After the volcanic eruption, pioneer species colonized the area and the ecosystem began to undergo succession. Succession occurs after a disturbance, such as a volcanic eruption, where the species change over time, beginning with colonization by pioneer species.

1.A Which of the following examples illustrates the community with the highest biodiversity?

Answer D explanation: Each species has 10 individuals, so this community has the highest species evenness and therefore the highest biodiversity since species richness is the same for all options. Biodiversity is determined by species richness (more species equals more diversity) and species evenness (the more evenly distributed the number of individuals of each species is, the more diversity in the community). All options have 5 species and 50 individuals total and vary only by number of individuals of each species.

Estuary provides refuge after dam removal for bull trout Bull trout use a bewildering array of strategies to aid in their survival, from remaining in streams their whole lives, like rainbow trout, to spending part of their lives in the ocean before returning to streams to spawn, just as salmon do. Bull trout are present in only one of two neighboring rivers in the Olympic peninsula, Washington state, and in this one (the Elwha River), where two large dams were removed. Dam removal resulted in massive outflow of sediments, reducing the clarity of the water and also building up a large delta and expanding the size of the estuary at the mouth of the Elwha River. Sampling for bull trout before, during, and after dam removal was used to detect whether bull trout changed their use of the Elwha River estuary or moved into the adjacent Salt Creek stream where they were formerly absent. Sampling revealed no movement into Salt Creek, but numbers of bull trout in the Elwha River estuary increased greatly during and immediately after dam removal, coinciding with large sediment outflow, before returning to their original low levels. Thus, bull trout appear to have used the enlarged estuary as a refuge from the effects of dam removal, then returning to the river when the river water cleared up from the sediment. Of additional interest is the long-term response of bull trout to the additional habitat opened up above the former dams. Which of the following best identifies the author's claim?

Bull trout are unable to live in high sediment loaded waters and migrated to avoid the conditions introduced during dam deconstruction. The article states that the bull trout avoided the highly sedimented river by migrating to the estuary when the sediment load was high and then returned to the river when the water had less turbidity.

Which of the following best explains how environmental stressors, such as wildfires, can affect biodiversity in an ecosystem?

Ecosystems with more species diversity are more likely to recover after a disturbance than ecosystems with low species diversity explanation: Ecosystems with more species have greater stability and are more likely to maintain communities and food webs after a disturbance.

Which of the following would most likely result from the deforestation of large areas of tropical rain forests caused by slash-and-burn agriculture?

Increased global temperature because of the release of CO2 explanation: CO2 is released during the burning of tropical rain forests and is a greenhouse gas.

Based on the data shown in the graph, when would the species richness of the ecosystem have been the lowest?

One to four years after the volcanic eruption The number of plant species present was the lowest one year after the volcano erupted and remained under 100 species for 10 years after the eruption.

A 163163 square-kilometer (km2) small island is found 2,000km2,000km from the mainland. A second, larger, 230,000km2230,000km2 island is found 1,000km1,000km from the mainland. Based on the theory of island biogeography, which of the following statements is most likely true about the small island when compared with the large island?

The rate of immigration is lower for the small island than for the large island. explanation: More species would migrate to this large island over the small one since the large island is closer and larger.

Very Large Dead Zone Forecast for the Gulf of Mexico Scientists at the National Oceanic and Atmospheric Administration (NOAA)(NOAA) are forecasting this summer's Gulf of Mexico hypoxic zone or "dead zone"—an area of low to no oxygen that can kill fish and other marine life—to be approximately 7,8297,829 square miles, or roughly the size of Massachusetts. The annual prediction is based on United States Geological Survey river flow and nutrient data. The 2019 forecast is close to the record size of 8,7768,776 square miles set in 2017 and larger than the five-year average measured size of 5,7705,770 square miles. The annually recurring Gulf of Mexico hypoxic zone is primarily caused by excess nutrient pollution from human activities, such as urbanization and agriculture, occurring throughout the Mississippi River watershed. Once the excess nutrients reach the gulf, they stimulate an overgrowth of algae, which eventually die, then sink and decompose in the water. The resulting low oxygen levels near the bottom are insufficient to support most marine life and have long-term impacts on living marine resources that are unable to leave the area. A major factor contributing to the large dead zone this year is the high amount of spring rainfall in many parts of he Mississippi River watershed, which led to record high river flows and much larger nutrient loading to the Gulf of Mexico. This past May, discharge in the Mississippi and Atchafalaya rivers was about 6767 percent above the long-term average between 1980 and 2018. The latest National Climate Assessment predicts an increase in the frequency of very heavy precipitation events in the Midwest, Great Plains, and Southeast regions, which would impact nutrient input to the northern Gulf of Mexico and the size of the hypoxic zone." Which of the following best identifies the author's claim?

The increased rainfall events in the United States are decreasing the tolerance of fish and other marine species in the Gulf of Mexico because of a decreased concentration of oxygen. explanation: The article states that the forecasted large hypoxic zone is a result of the high amount of spring rainfall this year and that the frequency of heavy rainfalls is predicted to increase. Heavy rainfall will lead to more nutrient loading into the Gulf of Mexico, which will lead to a decreased oxygen concentration in the water, thereby increasing ecological stress on marine organisms. Fish species have a range of oxygen concentrations they can tolerate, and outside of this range, the species are less likely to survive.

Which of the following statements correctly describes the trends seen in the data?

The lowest sea level occurred during the Paleogene period. It is the point furthest to the left on the curve, indicating the lowest sea level based on the relative scale shown in the graph.

Which of the following statements best explains the changes in the size and composition of the population of finches after the drought?

The total number of finches in the population decreased, and the larger-beaked finches were more successful in the drier environment.

Based on the theory of island biogeography, which of the following is the most likely reason that an island in the ocean that is 5 kilometers from a continent would have a higher number of species than one that is 15 kilometers from a continent?

There are more species that have the ability to travel 5 kilometers than can travel 15 kilometers. explanation: It takes less energy and potentially less complicated locomotion to travel 5 kilometers than it does 15 kilometers, so more species are able to travel 5 kilometers than 15 kilometers.